Treatise On Conscience

36. • DEFINITION. Conscience is the practical dictate of reason, or a practical judgment by which we judge that something can or ought to be done, because it is good or commanded, or that it must be omitted, because it is evil ¹. - Hence it differs from synderesis, which dictates only general principles.

¹ The necessity of some conscience, that is, of a judgment about the honesty or dishonesty of an action, for moral good or evil is manifest. For an act cannot be imputed to a man of which he is not master. But man is master of his own acts through free will, by which he determines himself. But there is not nor can there be any will of that honesty or dishonesty which the agent does not know, since the will is not borne into the unknown. Therefore no honesty or dishonesty (understand formal, not merely material), or no moral good or evil, can be present in acts unless and insofar as some judgment of reason concerning their honesty or dishonesty precedes them. And thus indeed according to the first and best-known elements of philosophy and moral theology, indeed also of the sense common to the human race. Although these things are most manifest, nevertheless there was reserved to Italy in our age this most unhappy distinction, that, dressed in a philosophical mantle and as though restoring collapsed moral science, a doctrine should range through it with impunity, by force of which moral acts without any conscience must be admitted, and indeed acts which are to be judged not only morally good or evil, but also meritorious or demeritorious, and yet were elicited without any otherwise preceding judgment concerning their honesty or dishonesty! In what way these things cohere with Catholic dogma, others certainly may see; as to the philosophizing, let this for the present be sufficient for us to oppose to it: How empty it is in things!

Division. Conscience is distinguished:

1. Right, or erroneous, according as it dictates the true or the false ².

² Some wish to oppose true rather than right to erroneous; because they contend that right conscience is present also in those who act from invincibly erroneous conscience. The matter, as is clear, is about a manner of speaking.

2. Certain, or doubtful, according as the mind firmly judges that something is good or evil, or, on the contrary, suspended, hesitates concerning the honesty of an action.

3. Scrupulous, or lax, according as either from an empty motive it apprehends sin where there is none, or on the contrary, for a slighter cause, presumes sin to be absent, or holds as light what is grave.

4. Probable, or improbable, according as from a grave or weak motive the mind is inclined to opine ³. - Of each separately ⁴.

³ Common usage has it that probability or improbability be said of opinion rather than of conscience.

⁴ A distinction must not be omitted which recurs everywhere among the Authors, namely, that conscience is called either antecedent or consequent, according as judgment concerning the honesty of the act either precedes the act itself or follows it. On this matter the Christian people must certainly be taught that the formal goodness of acts

Beautifully St. Thomas (I, q. 79, art. 13) thus describes the offices of both antecedent and consequent conscience: Conscience is said to testify, to bind or incite, or also to accuse, or also to bite back or reprove. And all these things follow upon the application of some cognition or knowledge of ours to those things which we do. This application indeed happens in three ways: in one way according as we recognize that we have done something or have not done it...; and according to this conscience is said to testify (here you have consequent conscience, although not moral). In another way it is applied according as through our conscience we judge that something must be done; and according to this conscience is said to bind or incite (this pertains to antecedent conscience). In a third way it is applied according as through conscience we judge that something which has been done was well done or not well done; and according to this conscience is said to excuse or accuse, or to bite back (which things pertain to consequent conscience).

or malice is not taken from consequent conscience, but from antecedent. For the uneducated are often deceived, who, while they either read books or hear sermons, judge that they have sinned in certain things, when during the act they had never thought about the malice of those acts, or certainly about some gravity of fault, nor had suspected it.